A vehicle, such as an automobile, includes a frame and an underbody supported by the frame. The vehicle typically includes a subframe for supporting various components of an engine, drivetrain, and/or suspension of the vehicle. The subframe is typically mounted to the underbody of the vehicle with bolts, welding, etc. The subframe extends forwardly from the underbody toward a front bumper of the vehicle.
During impacts of a front of the vehicle, such as those defined by Federal Motor Vehicle Safety Standards (FMVSS) and Insurance Institute for Highway Safety (IIHS) standards including frontal impacts, angular frontal impact, small offset rigid barrier (SORB) impact, etc., front structural components of the vehicle may deform to absorb energy. In one type of configuration, the subframe of the vehicle is not designed to detach from the underbody. Such designs typically require additional energy absorbing features and restraint systems to properly handle energy during a frontal impact. For example, this type of subframe may transmit a larger pulse to the vehicle during a frontal impact, and this larger pulse may be addressed with the additional energy absorbing features and/or restraint systems.
In another type of configuration, the subframe is designed to detach from the underbody during frontal impact to lower the pulse and Vehicle Pulse Index during the frontal impact. Detachable subframes can be designed to shear the connection between the subframe and the underbody; however, this shearing can create design difficulties. There remains an opportunity to design a subframe that effectively detaches from the underbody during frontal impact.